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just finished debugging & repaired a friend's mini3..sorry for keeping the mini3 with me for so so so so long. i hate exam! lol

problems are as follow:

Left side no sound

HIGH Voltage Output at Left Channel

after re-solder all soldering points, make sure no cold soldering or short circuit , power up and test.. well, results are the SAME no sound no sound!!

alright, last try is to change the OPA AD8397! mini3 is well known in burning OPA. lol

SOIC OPA not easy to de-solder without proper smd remover tools..traditional method is to apply huge amount of solder on top and bottom of the SOIC, and "try" to remove it by heating up the solder...hm..i'm not good in describing, just REMOVE IT!! wahaha

after changing the OPA, measure OR-OL-OG to Gnd, all within recommended range. plug in my senn earbud with mp3 input~~~

wow~~it works wonder now!!!

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SOIC OPA not easy to de-solder without proper smd remover tools..traditional method is to apply huge amount of solder on top and bottom of the SOIC, and "try" to remove it by heating up the solder...hm..i'm not good in describing, just REMOVE IT!! wahaha

Glad your Mini3 is working. Having killed so many AD8397 in my PINTs and Mini3, I found the easiest way for me is to

1. remove all the tall components near the chip.

2. insert a paper cutter blade under the chip.

3. Apply soldering iron to all 4 leads on same side at the same time by angling the iron as horizontally as possible

4. the solder on all 4 leads will melt after a few seconds. Gently pry the chip with the blade so that it bends on the 4 leads still soldered.

5. Grip the chip with a tweezer and now heat the remaining 4 legs at the same time with the iron. When the solder melts, lift the chip with the tweezer.

6. Clean the pads with solder wick.

Remember the key word is "gentle". Apply too much pressure and the solder pads on the pcb will be lifted. Hope this is helpful to those clumsy like me.

Edited May 7, 2008 by heady

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I'm using a different method, I added a tiny ball of lead to the pads, heat the pad up to absorb the ball so more solder ends up on the pad, place the opamp in place, keep it in place with a pair of tweezers and than use the iron to press the pins down one by one. No problem with the continuity though. Not confident with the flooding method as I'm afraid of creating a short between the pins.

BTW, I desoldered C5+ and C5-, not sure how to test if it's faulty or not but when I set it to DCV 200mv, one measures 190+mv and the other measures 10+mv. Does this mean the cap is faulty?